1. Field of the Invention
The field of the invention is agriculture, particularly fertilizers.
2. Background
In agriculture, it is often desirable to use land that is not initially optimal in terms of soil fertility. Fertilizers have been developed for use on such land. Fertilizers are materials that are used to supply elements needed for plant nutrition. Fertilizer materials may be in the form of solids, semi-solids, slurry suspensions, pure liquids, aqueous solutions and gases. Fertilizing materials may be introduced into a plant s environment in a number of different ways, including through addition to the soil, through application directly to a plant s foliage, and the like. The use of fertilizers is critical to commercial agriculture as fertilizers are essential to correct natural deficiencies and/or replace components in soil. A number of different types of fertilizer compositions have been developed and employed in agriculture. However, there is continued interest in the development of new fertilizer compositions.
Another problem encountered by farmers and other agricultural workers is soil infestation with deleterious pests and/or pathogens. A variety of synthetic chemical pesticides have been developed over the years to treat pest or pathogen infested soils. While such synthetic chemicals have been used with success, their use is not without controversy. Specifically, there is increasing public concern over the potential link between pesticide use and human disease conditions. As such, there is continued interest in the identification of new compositions which are capable of controlling soil borne pests or pathogens.
Relevant Literature
U.S. Patents of interest include: U.S. Pat. Nos. 5,549,729; 5,582,627; 5,696,094; 5,797,976; the disclosure of which are herein incorporated by reference.
Soil amendment compositions and methods for their use are provided. The subject compositions are aqueous compositions that include a predisposing agent, a carbon skeleton energy component and a vitamin-cofactor component. The subject compositions find use in a variety of different applications, including: the control of soil borne pests or pathogens; the neutralization and/or degradation of toxins; the improvement of soil characteristics, e.g. water permeability; the improvement of soil fertility; etc.
Aqueous compositions and methods for their use in soil amendment applications are provided. The subject compositions include a predisposing agent, a carbon-skeleton energy (CSE) source and a vitamin co-factor component. The subject compositions find use in a variety of different soil amendment applications, where such applications include: reducing the population of soil borne pests or pathogens; neutralizing or degrading soil toxins; improving soil characteristics; improving soil fertility; and the like. In further describing the invention, the compositions are described first in greater detail followed by a discussion of representative soil amendment methods in which the subject compositions find use.
Before the subject invention is described further, it is to be understood that the invention is not limited to the particular embodiments of the invention described below, as variations of the particular embodiments may be made and still fall within the scope of the appended claims. It is also to be understood that the terminology employed is for the purpose of describing particular embodiments, and is not intended to be limiting. Instead, the scope of the present invention will be established by the appended claims.
In this specification and the appended claims, the singular forms xe2x80x9ca,xe2x80x9d xe2x80x9canxe2x80x9d and xe2x80x9cthexe2x80x9d include plural reference unless the context clearly dictates otherwise. Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood to one of ordinary skill in the art to which this invention belongs.
A feature component of the subject aqueous compositions is the predisposing agent. By predisposing agent is meant an agent which can traverse the membranes of a target pest or pathogen and thereby weaken the pest or pathogen physiology by virtue of denaturation of key enzymes (e.g. cytochrome oxidase) and/or proteins, and the like. A variety of different compounds are capable of fulfilling the above functional requirements and thereby serving as predisposing agents. As such, predisposing agents of interest include: aromatic amino acids, e.g. tyrosine, phenylalanine, tryptophan; phenols and derivatives and general products or reactants of the Shikimic Acid Pathway, e.g. cinnamic acid, chlorogenic acid, caffeic acid, coumaric acid, catechuic acid, ferulic acid, chorismic acid, quinic acid, gallic acid, gallotannins, scopeletin, dicoumarol, preocenes, phytoalexins such as orchinol, phaseolin, pisatin, isocoumarin, and the like; lignin alcohols e.g. coniferyl, sinapyl, p-coumaryl; flavonoids e.g. cyanidin, anthocyanidin, pelargonidin, delphinidin, malidin, peonidin, petunidin; flavonols and flavones; betalains e.g. betacyanin, betalain, betaxanthin; alkaloids e.g. caffeine, nicotine, theobromine; limonene-1-Methyl-4-(1-Methylethenyl)cyclohexene; p-mentha-1,8-diene; lignosulfonates, e.g. calcium lignosulfonate, potassium lignosulfonate, sodium lignosulfonate, ammonium lignosulfonate; and the like. Also of interest as predisposing agents are members and/or products of the pentose phosphate pathway, as well as derivatives or analogues thereof, where representative agents of interest include, but are not limited to: glucose-6-phosphate; D-Glucono-1,5-lactone 6-phosphate; 6-Phospho-D-gluconate; D-Ribulose 5-phosphate; ribose-5-phosphate; fructose-6-phosphate; glyceraldehyde-3-phosphate; NADPH; and the like.
The subject compositions may include a single predisposing agent or a plurality of different predisposing agents. When a plurality of different predisposing agents are employed, the number of different predisposing agents may range from about 2 to 6, usually from about 2 to 5 and more usually from about 2 to 4.
The total amount of predisposing agent(s) that is present in the subject compositions is sufficient to achieve the desired weakening in the target pest or pathogen present in the soil. Generally, the amount present in the composition is sufficient to achieve a concentration in the soil following treatment ranging from about 5 to 650 ppm, usually from about 10 to 350 ppm and more usually from about 25 to 200 ppm. The amount of predisposing agent present in the composition may vary depending on whether the composition is to be applied as is to the soil or diluted prior to application, e.g. where the composition is a concentrate, as described infra. However, in many embodiments, the total amount of predisposing agent present in the composition ranges from about 5 to 75, usually from about 10 to 60 and more usually from about 15 to 60% w/w of the composition.
A particularly preferred predisposing agent in many embodiments of the invention is a lignosulfonate. Lignosulfonates of interest include: calcium lignosulfonate, potassium lignosulfonate, sodium lignosulfonate, ammonium lignosulfonate; and the like. The lignosulfonate is generally present in the composition in an amount that is sufficient to achieve a concentration in the soil following application that ranges from about 5 to 650 ppm, usually from about 10 to 350 ppm and more usually from about 25 to 200 ppm. In many embodiments, the amount of lignosulfonate present in the composition ranges from about 5 to 75% w/w, usually from about 10 to 50% w/w and more usually from about 15 to 60% w/w of the composition. Lignosulfonates are generally available from Westway Terminal, Stockton Calif.; PM Ag, Stockton Calif.; Georgia Pacific, Bellingham Wash.; and the like.
Also of particular interest as a predisposing agent is gallic acid. When present, gallic acid is present in an amount sufficient to achieve a soil concentration ranging from about 0.05 to 5.0 ppm, usually from about 0.1 to 5.0 ppm and more usually from about 0.2 to 1.0 ppm. In many embodiments, the amount of gallic acid present in the composition ranges from about 0.001 to 15% w/w, usually from about 0.001 to 10% w/w and more usually from about 0.01 to 10% w/w.
In a particularly preferred embodiment, the subject soil amendment compositions include both a lignosulfonate and gallic acid. In such embodiments, the amounts of each of these agents in the composition are sufficient to achieve a lignosulfonate concentration in the treated soil that ranges from about 10 to 650 ppm and a gallic acid concentration in the soil that ranges from about 0.05 to 5.0 ppm. In many compositions falling within the scope of this preferred embodiment, the amount of lignosulfonate ranges from about 10 to 50% w/w of the composition while the amount of gallic acid ranges from about 0.001 to 10% w/w of the composition.
A second feature component of the subject compositions is the carbon skeleton energy (CSE) component. CSE components that find use in the subject compositions are carbon containing substances which provide a readily assimilable source of both carbon and energy for promoting microbial proliferation. Preferably, the CSE component provides a complex array of various carbon compounds such that varied enzymology is induced in microbes present in the target soil. As such, CSE sources that favor ancestral, beneficial species, which normally carry complex enzyme systems (as opposed to more simplified forms hosted by facultative pathogens) are particularly preferred. Generally, the carbon skeleton energy component is a C2 to C10, usually C4 to C8 compound or polymer thereof, e.g. a polymer in which the monomeric units are C2 to C10 compounds, such as a polysaccharide. The CSE component may be a single carbon containing compound or a composition of two or more different carbon containing or organic compounds. Compounds and compositions capable of serving as a CSE component include: complex organic compositions, such as molasses (e.g. cane, sugar beet, sorghum, etc.), whey, corn steep liquor, grape syrup, maple syrup, corn syrup, etc; sugars, e.g. sucrose, fructose, glucose, lactose, galactose, dextrose, maltose, raffinose, ribose, ribulose, xylulose, xylose, amylose, arabinose, etc.; sugar phosphates, e.g. fucose-P, galactose-P, glucose-P, lactose-P, maltose-P, mannose-P, ribose-P, ribulose-P, xylose-P, xylulose-P, etc.; sugar alcohols, e.g. adonitol, sorbitol, mannitol, maltitol, ribitol, galactitol, glucitol, etc.; organic acids, e.g. gluccuronic acid, alpha ketoglutaric acid, galactonic acid, glucaric acid, gluconic acid, pyruvic acid, polygalacturonic acid, citric acid, succinic acid, malic acid, isocitric acid, folic acid, etc.; nucleotides and bases, e.g. adenosine, adenosine-P, uridine, uridine-P, thymine, thymine-P, cytosine, cytosine-P, guanine, guanine-P, etc.; and amino acids, e.g. glycine, alanine, leucine, isoleucine, asparagine, tyrosine, phenylalanine, serine, cysteine, valine, proline, methionine, glutamine, threonine, lysine, aspartic acid, glutamic acid, arginine, and the like.
The CSE component is present in an amount sufficient to provide for a concentration in the target soil upon application that ranges from about 5 to 650 ppm, usually from about 10 to 350 ppm and more usually from about 25 to 200 ppm. In many embodiments, the amount of CSE component in the composition ranges from about 5 to 75% w/w, usually from about 10 to 50% w/w and more usually from about 15 to 60% w/w.
In a preferred embodiment, the CSE source is a molasses. Molasses may be obtained from a number of commercial sources, including cane molasses, etc., where commercial sources of molasses include: Westway Terminal, Stockton Calif.; PM Ag, Stockton, Calif.; and the like.
The final component is a vitamin-cofactor. A variety of agents are capable of serving as the vitamin-cofactor component of the subject aqueous compositions. Such agents include: yeast extract, yeast, vitamin Bs, e.g. thiamine pyrophosphate, riboflavin, biotin, pantothenic acid, phosphatidylcholine, inositol, PABA, nicotinic acid, folic acid and mixtures thereof, and the like. Of particular interest as a vitamin-cofactor is yeast extract, particularly yeast extract obtained from spray dried extract, as available from Feedstuffs, Inc., Stockton Calif.; California Spray Dry, Stockton, Calif.; and the like. The amount of vitamin-cofactor component present in the composition is sufficient to provide a concentration in the treated soil that ranges from about 0.01 to 10 ppm, usually from about 0.01 to 5.0 ppm and more usually from about 0.01 to 1 ppm. The amount of vitamin co-factor present in the composition generally ranges from about 0.001 to 15% w/w, usually from about 0.001% to 10% w/w and more usually from about 0.01 to 5.0% w/w.
Importantly, the composition includes substantially no macronutrients, e.g. nitrogen, potassium, phosphorous; or micronutrients, e.g. zinc, iron or manganese. By substantially no is meant that the amount of any one of these elements, if present in the composition, is insufficient for the element to influence the overall activity of the composition or the amendment of the target soil, i.e. the amount of the component is insufficient to make the component an active ingredient of the composition. As such, for nitrogen, phosphorous and potassium, the amount present in the composition, if present at all, does not exceed about 5% and preferably does not exceed about 2.5%, and more preferably does not exceed about 1%, 0.5% or 0.25%. For iron, zinc and manganese, the amount present in the composition, if present at all, does not exceed about 2% and preferably does not exceed about 1% and more preferably does not exceed about 0.5% or 0.25%. In many embodiments, the compositions will have none of these macronutrient and micronutrient components. Despite the lack of these macro- and micronutrients, the composition exhibits significant soil amendment activity.
As the subject compositions are aqueous compositions, they further include a substantial amount of water. The amount of water present in the composition may vary depending on whether the composition is a concentrated or dilute composition. Generally, the compositions include at least about 5%, usually at least about 20% and more usually at least about 30% water, where the amount of water present in the composition may be as high as 80% or higher, but generally does not exceed about 70% and usually does not exceed about 40%.
The above soil amendment compositions are prepared by combining water with the various agents under conditions sufficient to produce an aqueous solution containing the various agents. The water that is used to produce the subject compositions may be tap water obtained from any convenient water source, e.g. a municipal water district, where the water may be purified or otherwise treated, e.g. to remove certain undesirable agents that may be initially present therein. The various agents to be solubilized in the water to produce the soil amendment compositions may be obtained from any convenient source, e.g. commercial vendor. For example, the carbohydrate component may be derived from a commercially available carbohydrate source, such as commercially available molasses, etc.
In preparing the subject soil fertilizer compositions, a concentrated or parent composition may first be produced, which parent composition or mix may or may not be diluted with water.
The subject aqueous compositions find use in a variety of soil amendment applications, i.e. methods of improving soil. In practicing the subject methods, the aqueous composition is contacted with the soil under conditions sufficient to achieve the desired concentrations of the agents of the composition in the soil. By contact is meant that the composition is introduced into the soil such that the desired concentration of the disparate components of the composition is obtained in the soil. As such, contact can include spraying so that the composition soaks into the soil, injecting the composition into the soil, flooding the soil with the composition, and the like. Contact is performed such that the concentration in the soil of the predisposing agent following treatment is at least about 5 ppm, usually at least about 20 ppm and more usually at least about 60 ppm, where the concentration of the predisposing agent following treatment may be as high as 650 ppm or higher, but generally does not exceed about 200 ppm and usually does not exceed about 60 ppm. Contacting also results in a concentration of the CSE component in the soil that is at least about 5 ppm, usually at least about 20 ppm and more usually at least about 60 ppm, where contact may result in a concentration of the CSE component that is 650 ppm or higher, but generally does not exceed about 200 ppm and usually does not exceed about 60 ppm. In addition, contact of the composition with the soil results in a vitamin-cofactor concentration in the soil that is at least about 0.01 ppm, usually at least about 0.05 ppm and more usually at least about 1.0 ppm, where the vitamin-cofactor concentration may be as high as 10 ppm or higher, but generally does not exceed about 5.0 ppm and usually does not exceed about 1.0 ppm.
The amount of aqueous composition that is used during any one application will vary greatly depending on the nature of the soil, the nature of the composition, the environmental conditions, etc. Where crops are treated with the subject compositions, the amount that is applied based on treated acreage is generally at least about 5 to 240 gal per acre, usually at least about 10 to 120 gal per acre, and more usually at least about 20 to 60 gal per acre, where the amount that is applied may be as high as 480 gal per acre or higher, but will usually not exceed about 240 gal per acre.
Depending on the nature of the soil, the nature of the composition, and the environmental conditions, as well as other factors, the composition may be applied more than once over a given period of time. As such, the composition may be applied daily, weekly, every two weeks, monthly etc.
The aqueous compositions of the subject invention find use in a variety of different applications, where such applications include: the control of soil borne pests and pathogens; the improvement of water filtration; the improvement in mineral release; the enhancement in the water holding capacity of soil; the mellowing of soil textural qualities; the enhancement of the decomposition of plant tissues and accelerated degradation of potentially toxic chemicals and/or allelopathic chemicals; the improvement of root mass in plants grown in treated soil; and the like.
A variety of different soil borne pests may be controlled with the subject compositions. Such pests include: plant parasitic nematodes, phylloxera, grubs, and the like. By contolled is meant that the pest population in the soil is reduced, generally by at least about 5%, usually at least about 25% and more usually at least about 50%. As such, the invention provides methods and compositions for at least reducing, if not substantially eliminating, the population of soil borne pests in soil.
Similarly, the subject methods and compositions provide means for reducing the amount of pathogen present in soil. Pathogens that can be targeted with the subject methods include: pathogenic fungi, actinomycetes, bacteria, viruses, and the like. The subject methods result in a reduction of at least about 5%, usually at least about 25%, and more usually at least about 50% of the amount of pathogen in the soil.
Also provides by the subject invention are methods and compositions for increasing indigenous soil microbe populations. Beneficial microbes whose population may be increased by the subject invention include: bacteria, fungi, actinomycetes, various free-living invertebrates, and the like. Applying the composition to the soil according to the subject methods results in at least a 2-fold increase, usually at least about a 20-fold increase and more usually at least about 40-fold increase in the microbe population in the treated soil.
The subject methods and compositions can also be used to improve water filtration through the soil. Water filtration may be improved by at least about 1.5xc3x97, usually at least about 2.5xc3x97 and more usually at least about 4.5xc3x97.
Soil mineral release can also be enhanced using the subject methods and compositions. Mineral release, e.g. the release of minerals such as calcium, potassium and phosphorous, can be improved by at least about 1.5xc3x97, usually at least about 3.0xc3x97 and more usually at least about 5.0xc3x97 as compared to that observed in control soil.
Finally, the subject methods and compositions can be used to increase the root mas of plants grown in the treated soil. Generally, the subject methods result in an increase in root mass of at least about 1.5xc3x97, usually at least about 2.0xc3x97 and more usually at least about 4.0xc3x97 as compared to control plants, i.e. plants grown in untreated but otherwise substantially identical soil.
The following experiments are offered by way of illustration and not by way of limitation.